Along with running an Ubisoft promotion that includes some decent bundle discounts and special daily deals, Steam has savings on various indie titles including 50% off and free access to Ace of Spades this weekend. Green Man Gaming also has bargains on a slew of indie games, GamersGate offers XCOM: Enemy Unknown for $20, GameFly has 75% off Total War titles and GOG is running a deal that lets you pick five games to score 80% off. Also of note, the latest Humble Bundle expires in a few days.

Steam
87  Assassin's Creed III $32.49 (35% off)
81  Tom Clancy Franchise Pack $94.99 (50% off)
78  Prince of Persia Complete Pack $34.99 (42% off)
88 Left 4 Dead 2 $4.99 (75% off)
83 Anno 2070 Complete Pack $34.99 (36% off)
67 Arcania + Gothic Pack $12.49 (75% off)
78 Might and Magic Heroes VI Gold $23.99 (40% off)
70 Sacred 2 Gold $6.79 (66% off)
84 Age of Empires III: Complete Collection $19.99 (50% off)
78 Endless Space $14.99 (50% off)
72 Shoot Many Robots $4.99 (50% off)
77  From Dust $3.74 (75% off -- today only)
88  Rayman Origins $6.79 (66% off-- today only)
I Am Alive $5.09 (66% off-- today only)
Ace of Spades $4.99 (50% off + free weekend)
F1 2012 $13.59 (66% off)
Little Inferno $3.99 (60% off)
Cargo Commander $3.39 (66% off)
Beyond Good and Evil $4.99 (50% off)
Babel Rising $4.99 (50% off)
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Amazon Digital
69 Payday The Heist 4-Pack $19.99 (75% off)
79 Hitman: Absolution $19.99 (50% off)
Bandai Pack $14.99 (84% off)
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GameStop
79 Warhammer 40,000 Dawn of War Collection $33.49 (33% off)
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GamersGate
88 XCOM: Enemy Unknown $19.98 (60% off)
83 Saints Row: The Third $7.49 (75% off)
68 Saints Row 2 $3.74 (75% off)
90 The Witcher 2: Assassins of Kings Enhanced Edition $11.97 (40% off)
87 The Witcher: Enhanced Edition Director's Cut $4.00 (60% off)
50 Resident Evil: Operation Raccoon City $24.98 (50% off)
84 Resident Evil 5 $9.98 (50% off)
79 Gratuitous Tank Battles $5.99 (70% off)
70  The Kings' Crusade $2.49 (75% off)
Victoria Complete $2.50 (75% off)
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GameFly
87 Medieval II: Total War $3.75 (75% off)
88 Total War: Shogun 2 $7.49 (75% off)
84 Total War: Shogun 2 - Fall of the Samurai $7.49 (75% off)
88 Empire: Total War $3.75 (75% off)
82 Napoleon: Total War $3.75 (75% off)
Rome: Total War $2.49 (75% off)
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Green Man Gaming
78  Dear Esther $1.38 (80% off)
82  Chivalry: Medieval Warfare $12.49 (50% off)
74  Dustforce $4.99 (50% off)
85 Frozen Synapse $6.23 (75% off)
77  Space Pirates and Zombies $5.08 (66% off)
78  Stacking $7.49 (50% off)
85  Super Meat Boy $3.74 (75% off)
81  Swords & Soldiers $2.49 (75% off)
80  Trine $1.24 (75% off)
74  Unstoppable Gorg $2.49 (75% off)
10,000,000 $2.49 (50% off)
Age of Fear 2: The Chaos Lord $9.99 (50% off)
Air Buccaneers $5.09 (66% off)
Awesomenauts $4.99 (50% off)
Forge $9.99 (50% off)
Giana Sisters: Twisted Dreams $5.09 (66% off)
Guns of Icarus Online $4.99 (75% off)
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Get Games
78 Gemini Rue $4.99 (75% off)
82 Lara Croft and the Guardian of Light $3.74 (75% off)
71 Quantum Conundrum $3.74 (75% off)
78 Prince of Persia $4.99 (75% off)
86 Prince of Persia: The Two Thrones $1.69 (66% off)
76 Prince of Persia: The Forgotten Sands $7.49 (75% off)
Broken Sword Trilogy $3.74 (75% off)
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GOG
Pick 5 games and save 80%
60% off Enlight titles